Vical Inc. of San Diego, Ca. is the largest GMP manufacturer of plasmid DNA for vaccine clinical trials in the world. We have manufactured GMP plasmid DNA vaccines that are being used or entering clinical trials for HIV (in the US and China), malaria (up to 9 plasmids), Ebola, WNV, and SARS. Vical has undertaken an internal Product Development Program that focuses on the control of CMV viremia and the reduction of CMV disease and associated complications in patients undergoing either hematopoietic cell (HCT) or solid organ transplantation (SOT). A Phase 1 SBIR (R43 AI058386) approved from Feb to July 2004 (originally planned for November 2003 to April 2004) supplied funds to assist us to develop a CMV DNA vaccine and prepare for IND filing. The final milestone for seeking a Phase II SBIR was IND allowance of the vaccine. That milestone was achieved in March 2004. The Phase II SBIR proposal will support that development of the Vical CMV immunotherapeutic vaccine through Phase 1 and Phase 2 trials over the next 3 years of development. Specifically, we plan to: 1) To move the Vical bivalent CMV vaccine with gB and pp65 genes (VCL-CB01) into Phase 1 clinical trials for evaluation of safety and immunogenicity. 2) To study VCL-CB01 in Phase 2 trials in the HCT population to determine potential endpoints for an efficacy trial 3) To develop a second generation trivalent CMV vaccine (VCL-CT01) encoding the gB, pp65, and IE1 genes 4) To advance either VCL-CB01 or VCL-CT01 in the SOT population in conjunction with the Collaborative Antiviral Study Group of the NIH.